Watch-case spring



(N0 Model.)

P. MUHR.

WATCH CASE SPRING.

No. 423.174. Patented Mar. 11, 1890.

llll Ill llr Ill PIILIII WITNESSES: Q a 0% N. PETERS, "Into-Lithograph. Wilmrpflon. D. C.

UNITED STATES PATENT OFFICE.

PHILIP MUHR, OF PHILADELPHIA, PENNSYLVANIA.

WATCH-CASE SPRING.

SPECIFICATION forming part of Letters Patent No. 423,174, dated March 1 1, 1890.

Application filed August 24, 1889. Serial No. 321,848. (No model.)

To all whom it may concern.-

Be it known that I, PHILIP MUHR, a citizen of the United States. residing in the city and county of Philadelphia, State of Pennsylvania,have invented a new and useful Improvement in Watch-Case Springs, which improvement is fully set forth in the following specification" and accompanying drawings.

My invention consists of the construction of watch-case springs whereby they are stiifened and strengthened and their durability vastly lengthened, as will be hereinafter set forth. t

Figure 1 represents a perspective view of watch-case springs embodying my invention. Fig. 2 represents a face view of the springs,

showing also a watch-case in dotted lines.

Fig. 3 represents a section on line .90 00, Fig. .l, on an enlarged scale.

Similar letters of reference indicate corresponding parts in the several figures.

Referring to the drawings, A and B designate the springs of a watch-case,the same being employed, respectively, for securing the back 0 and throwing out the same, which features, broadly considered, are well known in the art in the class of huntingcase watches. T

The back of each spring is formed with a rib ortongue D, formed integral therewith, the same extending aportion of the length of the spring, thus stilfening and strengthening the same without aifecting the remaining portion where the resiliency is required.

Connected with each spring is a segmental piece E, of metal or other suitable material, whose inner face is formed with a groove serving as a sheath to receive the rib or tongue D, said piece being also in contact with the back of the spring, forming areenforce. Openings are formed in the pieces E and tongue D and rivets or pins F passed through the same, whereby the pieces are attached to the tongues, the springs being connected with the watch-case by screws G, which pass through saidipieces E and tongue D and the center of the watch-case.

It will be seen that the springs may be secured in position in a firm, reliable, and durable manner, and they are strengthened and prevented from being fractured or broken, while the proper degree of resiliency is preserved. I Y

Having thus described my invention, whatI claim as new, and desire to secure by Letters Patent, is-

1. A watch-case spring having a tongue on its back and provided with a re-enforce piece covering said tongue, said parts being combined substantially as described.

2. A watch-case spring having a rib or tongue extending in the longitudinal direction thereof, and a piece which is applied to the back of the spring, provided with a groove to receive said rib or tongue, substantially as described.

3. A watch-case spring having a tongue or groove extending a portion of the length of' the same, acting as a brace or stiffener of the spring, leaving the remainder of the spring free for resiliency, substantially as described. 4. A watch-case spring having a tongue or rib at the back thereof, and a sheath which is connected with said spring and receives said tongue or rib and is attachable to the watch-case, substantially as described.

- PHILIP MUHR. \Vitnesses:

J oHN A. WIEDEnsrinIM, A. P. JENNINGS. 

